Finding the Fourth Proportional to 2,151.72, 2,969.52 and 1,220.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,151.72 : 2,969.52 = 1,220.28 : x
2. Step 2: Convert to fraction form
   2,151.72/2,969.52 = 1,220.28/x
3. Step 3: Cross multiply
   2,151.72x = 2,969.52 × 1,220.28
4. Step 4: Simplify right side
   2,151.72x = 3,623,645.87
5. Step 5: Solve for x
   x = 3,623,645.87/2,151.72
6. Step 6: Final answer
   x = 1,684.07